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Effect of reduction-oxidation treatment on the properties of VSb_3W-Al_2O_3 catalyst for propane ammoxidation

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Rare Metals 2010年第6期29卷 597-603页

作者： WANG Guojun ZHANG Shunhai MIAO Xiaochun GUO Yun LU Guanzhong Key Laboratory for advanced Materials and Research institute of industrial Catalysis East China University of Science and TechnologyShanghai 200237China Shanghai Research institute of Petrochemical technology China Petroleum & Chemical CorporationShanghai 201208China

VSb3W-Al2O3 catalysts for propane ammoxidation were prepared by the conventional slurry method and new slurry method, namely, the reduction-oxidation slurry method. The effect of preparation methods on the physicochemical properties of VSb3W-Al2O3 catalysts were studied by N2 adsorption, XRD, XPS and Raman spectroscopy, and their catalytic performance for the ammoxidation of propane to acrylonitrile were tested. Compared with the VSb3W-Al2O3 catalyst prepared by the conventional slurry method, the VSb3W-Al2O3 catalyst prepared by the reduction-oxidation slurry method exhibited better propane conversion and acrylonitrile selectivity. This is due to that the reduction-oxidation treatment was advantageous for obtaining low valence state vanadium and high valence state antimony to form more rutile SbVO4, which is a vital active phase for propane ammoxidation.

关键词： oxides catalysts physicochemical properties preparation method propane ammoxidation

RHEOLOGICAL BEHAVIOR OF EPOXY RESIN WATERBORNE DISPERSIONS

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Chinese Journal of Polymer science 2001年第5期19卷 471-476页

作者： Zhen-zhong Yang Yuan-ze Xu De-lu Zhao State Key Laboratory of Polymer Physics & Chemistry, Center for molecular science institute of Chemistry, Chinese Academy of sciences, Beijing 100080 China 中科院化学所高分子物理与化学国家重点实验室北京

The waterborne dispersions of epoxy resin were prepared by the phase inversion emulsification technique. Rheological behavior and its relationship with the structural change of the systems were studied. It was shown that the concentrated dispersions were highly viscoelastic and pseudoplastic, which was attributed to the formation of a physical network among the waterborne particles via hydrogen bond. The dilute dispersions were Newtonian fluids. The discrete clusters composed of small waterborne particles were found in diluted dispersions. With increasing solid content, there existed a structural transition via percolation through a cluster-cluster aggregation mode to form the physical network, which was qualitatively evidenced by the TEM morphologies.

关键词： epoxy resin waterborne dispersion rheological behavior cluster-cluster aggregation percolation transition

Numerical Simulation and Experimental Investigation of Springback in U-Channel Forming of Tailor Rolled Blank

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Journal of Iron and Steel Research(International) 2012年第9期19卷 8-12页

作者： ZHANG Hua-wei 1 , LIU Li-zhong 1 , HU Ping 1 , LIU Xiang-hua 2 ( 1.Faculty of Vehicle Engineering and Mechanics , State Key Laboratory of Structural Analysis for industrial Equipment , Dalian University of technology , Dalian 116024 , Liaoning , China 2.Research institute of science and technology , Northeastern University , Shenyang 110819 , Liaoning , China ) Faculty of Vehicle Engineering and Mechanics State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian Liaoning China Research institute of science and technology Northeastern University Shenyang Liaoning China

In order to grasp the springback rule of TRB ( tailor rolled blank ) parts after forming , the springback behavior of TRB was investigated by integrating such three means as theoretical research , numerical simulation and stamping *** theories of springback were *** stamping and springback processes of annealed 1.2 / 2.0mm TRB , 1.2mm and 2.0mm plates for U-channel were simulated , and the simulation results were compared with the *** results indicate that the springback of TRB falls in between those of the 1.2mm and 2.0mm *** is desirable for the TRB U-channel to have die clearance of 1.1times maximum blank thickness and friction coefficient of about 0.12 , and longer thickness transition zone is *** simulation data demonstrate reasonably good agreement with the experiments.

关键词： tailor rolled blank U-channel springback annealing

Relaxation of Chain Extension of Amorphous PET Fiber Above the Glass Transition Temperature

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Chinese Chemical Letters 2000年第10期11卷 925-928页

作者： Xin LINGHU, Jun ZHAO, Rui SONG, Qing Rong FAN (Polymer Physics Laboratory, Center of molecular science, institute of Chemistry, Chinese Academy of sciences, Beijing, 100080) Polymer Physics Laboratory Center of Molecular Science Institute of Chemistry Beijing 100080 China

The recovery of amorphous PET fiber in global chain orientation but nearly random segmental orientation (GOLR) state was studied by the hot shrinkage measurement above the glass transition temperature. The relaxation curves in the form of di-exponential decay were acquired and the change of two special times with the variation of treating temperature and residual recovery ratio ' was discussed.

关键词： GOLR state PET recovery of chain extension hot shrinkage measurement.

Silence of Synaptotagmin VII inhibits release of dense core vesicles in PC12 cells

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science China(Life sciences) 2009年第12期52卷 1156-1163页

作者： LI JiangLi1, XIAO Yang1, ZHOU Wei1, WU ZhengXing1, ZHANG RongYing1· & XU Tao1,2· 1 Key Laboratory of molecular Biophysics of the Ministry of Education, institute of Biophysics and Biochemistry, College of Life science and technology, Huazhong University of science and technology, Wuhan 430074, China 2 national Key Laboratory of Biomacromolecules, institute of Biophysics, Chinese Academy of sciences, Beijing 100101, China. Key Laboratory of molecular Biophysics of the Ministry of Education Institute of Biophysics and Biochemistry College of Life Science and Technology Huazhong University of Science and Technology Wuhan China national Key Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing China

Synaptotagmin VII (Syt VII), which has a higher Ca2+ affinity and slower disassembly kinetics with lipid than Syt I and Syt IX, was regarded as being uninvolved in synaptic vesicle (SV) exocytosis but instead possibly as a calcium sensor for the slower kinetic phase of dense core vesicles (DCVs) release. By using high temporal resolution capacitance and amperometry measurements, it was demonstrated that the knockdown of endogenous Syt VII attenuated the fusion of DCV with the plasma membrane, reduced the amplitude of the exocytotic burst of the Ca2+-triggered DCV release without affecting the slope of the sustained component, and blocked the fusion pore expansion. This suggests that Syt VII is the Ca2+ sensor of DCV fusion machinery and is an essential factor for the establishment and maintenance of the pool size of releasable DCVs in PC12 cells.

关键词： Synaptotagmin VII dense core vesicles exocytosis RNA-mediated interference (RNAi)

Neural correlates of “feeling-of-not-knowing”:Evidence from functional MRI

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science Bulletin 2003年第2期48卷 144-147页

作者： MRI LUO Jing1, Niki Kazuhisa2 & LUO Yuejia1,3 1. Laboratory of Mental Health, institute of Psychology, Chinese Acad-emy of sciences, Beijing 100101, China 2. Neuroscience Research institute, national institute of advanced In-dustrial science and technology (AIST), Japan 3. Lab Visual Information Processing, Chinese Academy of sciences, Beijing 100101, China Correspondence should be addressed to Luo Yuejia (e-mail:luoyj@***) Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing China Neuroscience Research institute National Institute of Advanced Industrial Science and Technology (AIST) Japan Lab Visual Information Processing Chinese Academy of Sciences Beijing China

The neural correlates of 揻eeling-of-not-knowing?(揊OnK? i.e. the feeling-of-knowing judgmentsthat accurately predicted 搉ot knowing?or 搈isses?in the criterion test) were investigated by the event-related fMRImethod through an RJR (recall-judgment-recognition) pro-cedure that adopted unrelated word pairs as materials. Re-sults revealed that, relative to the inaccurate 揊OnK?pre-dictions, the accurate ones were associated with activities in right ventral prefrontal cortex (PFC) and insula, the areas that were known to subserve cue specification in which the retrieval cues were converted into descriptors that couldbe used for direct memory search. This result implied that the accurate FOnK?predictions relayed more on cue specification?process than the inaccurate ones and was inconsistent with the cue familiarity heuristic hypothesis offeeling-of-knowing.

关键词： event-related fMRI feeling-of-knowing cue specifica-tion.

An optimization approach to cycle quality network chain based on improved SCOR model

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Progress in Natural science:Materials International 2009年第7期19卷 881-890页

作者： Renbin Xiao a, Zhengying Caib, Xinhui Zhangc a institute of Systems Engineering, Huazhong University of science and technology, Wuhan 430074, China b School of Management, Huazhong University of science and technology, Wuhan 430074, China c Department of Biomedical, industrial & Human Factors Engineering, Wright State University, Dayton, OH 45435, USA institute of Systems Engineering Huazhong University of Science and Technology Wuhan 430074 China School of Management Huazhong University of Science and Technology Wuhan 430074 China Department of Biomedical Industrial & Human Factors Engineering Wright State University Dayton OH 45435 USA

Based on the improved supply chain operations reference (SCOR) model, a network-topology structure of cycle quality chain operations reference (CQCOR) model is built up, which realizes the cycle operation by an added quality process of reverse manufacturing. The concept of cycle quality chain management is defined, and its cost structure is analyzed according to positive and reverse quality processes. If the quality level is controlled by the positive quality cost, then the reverse quality cost is a nonlinear function of quality level. All the quality processes are connected by acceptable probability, so the optimized objective function is described as a fuzzy multi-objective function comprising maximum of the total profit of quality chain, maximum of the recycling efficiency and maximum of environment protection and source saving. The effects of different quality policies on fuzzy rules are compared by a simplified example. When the policy of recycling efficiency dominates, the total quality profit will be less than that of maximum profit policy.

关键词： Quality chain Cycle operation Quality cost SCOR

Photogeneration of the free radicals and singlet oxygen by chrysophanol from rheum

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science China Chemistry 2004年第5期47卷 381-387页

作者： RAO Jing1,2, XIE Jie1, ZHAO Jingquan1 & ZHU Teng2 1. Key Laboratory of Photochemistry, Center for molecular science, institute of Chemistry, The Chinese Academy of sciences, Beijing 100080, China 2. University of science and technology Beijing, Beijing 10083, China Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences Beijing China University of science and technology Beijing Beijing China

In the current work, chryosphanol (MHAQ) was isolated and purified from rheum, and the photosensitization activities were studied. In nitrogen-saturated DMSO solution, irradia- tion of chryosphanol (MHAQ) with visible light (>430 nm) produced the semiquinone radical anions (MHAQ??), which was intensified significantly by an electron donor NADH, suggesting electron transfer between the excited and ground state photosensitizer molecules. In an air-saturated DMSO solution, superoxide radical anions (O2 ), trapped by DMPO, were detected. ?? It was proved that O2 was not originated from the singlet oxygen (1O2) but dependent on DMPO, ?? chrysophanol, oxygen and the irradiation time. The singlet oxygen and OH could also be pro- ? duced by the photosensitization of the photosensitizer. These suggest that chrysophanol pos- sesses the photosensitization activity via Type I mechanism and Type II mechanism. To evaluate the photosensitization activities of MHAQ, emodin and mixed anthraquinone derivatives ex- tracted from rheum, the relative productivities of O2 were estimated to be 1.8, 1.1 and 1.0 re- ?? spectively and the quantum yields for singlet oxygen to be 0.36, 0.53 and 0.14 respectively. Therefore, these low-cost pigments may be potentially used as phototherapeutic medicine for some kind of vascular diseases or photo-activated pesticides.

关键词： chrysophanol, ESR, semiquinone radical anions, superoxide radical anions, hydroxyl radical, singlet oxygen.

Large-eddy simulation of formation of three-dimensional aeolian sand ripples in a turbulent field

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science China(Physics,Mechanics & Astronomy) 2008年第8期51卷 945-960页

作者： WU ChuiJie1,WANG Ming2 & WANG Liang3 1 State Key Laboratory of Structural Analysis for industrial Equipment,Dalian University of technology,Dalian 116024,China 2 Yellow River institute of Hydraulic Research,Zhengzhou 450003,China 3 Research Center for Fluid Dynamics,science School,PLA University of science and technology,Nanjing 211101,China State Key Laboratory of Structural Analysis for industrial Equipment Dalian University of Technology Dalian China Yellow River institute of Hydraulic Research Zhengzhou China Research Center for Fluid Dynamics Science School PLA University of Science and Technology Nanjing China

With the method of large-eddy simulation,the equation of spherule motion and the method of immersed boundary condition,numerical simulations of three-dimen-sional turbulent aeolian motion and the formation of sand ripples under three-di-mensional turbulent wind and the mutual actions of saltation and creeping motion were carried out. The resulting sand ripples have the form that is flat on the upwind side and steep on the leeward,which is identical to the sand ripples in nature. We also realized the self-restoration process of three-dimensional sand ripples,which shows the correctness of the method of numerical simulation and the models of saltation and creeping. Finally,We analyzed the influence of sand ripples on the three-dimensional turbulent wind field,and found that due to the appearance and development of sand ripples,in the normal direction of ground there exists stronger energy exchange,and moreover,there is close correspondence between the forms of sand ripples and the vorticity close to the ground surface.

关键词： large-eddy simulation equation of spherule motion sand ripples saltation creep